Electric-arc lamp.



1T0 IODEL.

PATENTED MAY 3, 1904. I T. HAMILTON-ADAMS.

ELECTRIC ARG LAMP.

APPLICATION FILED AUG. 29, 1903.

Inventor.

UNITED STATES Patented May 3, 1904.

THOMAS HAMILTON-ADAMS, OF LONDON, ENGLAND.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Ifatent No. 758,644, dated-May 3, 1904.

Application filed August 29, 1903. erial No. 171,260. (No model.)

To aJ/Z- whom it may concern.-

Be it known that I, THoMAs HAMILTON- ADAMs, a subject of the King of Great Britain, residing at Howard House, Arundel street. Strand, London, England, have invented new and useful Improvements in Electric Arc Lamps, of which the following is a specification.

My invention relates to electric-arc lamps of the kind in which the regulation of the car bons is eifected by an armature or core controlled by magnetic action.

According to my present invention I substitute for the usual solenoid two coils with tubular iron linings and connected in series which when the current flows through the coils are magnetized, the said coils being wound in the same direction and placed one above the other.at a suitable distance apart and mounted on a tube of non-magnetic material. This tube also forms-the guide for an armature or core which when the iron linings are not magnetized is partially contained within one of the said linings, one end projecting into proximity to the other lining. With this arrangement when a current flows through the coils the linings. and the armature are all magnetized in such a manner that the armature is acted upon by both magnets in the same direction, this action beingintensified, owing to the magnetization of the armature itself.

In the accompanying drawing I have shown diagrammatically one form of arc-lamp provided with the above-described improvements.

64 represents the frame of the lamp, 6 the lowercarbon, which is fixed therein, and 0 the upper or movable carbon.

(Z and e are the two coils which are wound around the two tubular iron linings or rings f and g, respectively, in the same direction and connected in series, and ii is the tube of non-magnetic material which incloses the carbon 0 and upon which the two iron linings f and g are fitted at a suitable distance apart, as illustrated in the figure.

z' is the. armature or core, which is here shown in the form of a clutch comprising two pivoted members, which embrace the carbon 0. This armature when the iron linings f and g are not magnetized is situated partially within the lining g, the outer or upper end'thereof extending into proximity to the lining f.

When the current is passed through the two coils, which, as before stated, are similarly wound and connected in series, the rings within the same are magnetized and will havetheir polarities similarly disposed. The adjacent poles of the two ringsto wit, theinner poleswill therefore be of opposite polarity. The core is so situated when no current is passing through the solenoids that it is within'the lowermost ring and does not reach to the upper ring. When the current is passed through the solenoids, this core is also magnetized, and its polarity will correspond to that of the two iron rings. The magnetized rings now begin to exert an upward pull on the core, as follows: The outer or lower pole of the lower ring will repel thelower end of the core, which is of like polarity, and push it upward. The

'inner or upper-pole of said lower ring being of opposite polarity to the lower pole of the core will attract it upward. The inner (or lower) pole of the upper ring being of opposite polarity to the upper end of the core will attract it and draw it upward. All these combined actions will cause the core to move upward until the upper end of the core passes the lower or inner pole of the upper ring, when the attraction of the latter on the core will tend to draw it downward, and as the core continues to rise it will be repelled by the upper or outer pole of the upper ring, which is of like polarity with the upper end of the core, thus increasing the downward pull, while'the upward pull has necessarily decreased. It follows, therefore, that when the pull of the two rings on the core becomes equalized the core will come into a condition of equilibrium. As the force exerted in one direction upon the core is gradually decreased as the force exerted in the upper direction increases, there is no danger of overpull, and the core will move smoothly and quickly into its balanced position. When the armature is in the form of a clutch, as in the arrangement illustrated, the pull upon it also simultaneously tightens it upon the carbon 0, which is thus moved with it.

One of the great advantages resulting from my invention is that I overcome the pumping action due to overpull on the armature and which has heretofore been compensated for by the employment of a dash-pot. By properly adjusting the relative positions of the armature and iron rings according to the length of are required the magnetic attractions and repulsions between the armature and rings themselves bring the former to rest when the are is struck, thus obviating the use of the dash-pots.

Although the drawing shows my improve ments applied to an arc-lamp of the kind wherein the movable carbon is directly controlled by a clutch-armature, I wish it to be distinctly understood that the invention is equally applicable to arc-lamps of the kind wherein the armature controls the carbon through the medium of intermediate mechanism.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is- 1. In an arc-lamp, the combination with a pair of coils wound in the same direction and connected in series, said coils forming the only coils of the lamp for controlling the movable carbon, of an armature-core for controlling the movable carbon adapted to move longitudinally through said coils, whereby when current is passed through said coils they operate in conjunction to bring the core into a state of equilibrium, substantially as described.

2. In an arc-lamp, the combination with a pair of coils wound in the same direction, connected in series and arranged in line with each other longitudinally, with a space between them, of an armature-core for controlling the movable carbon, arranged to move longitudinally through said coils, whereby said coils operate in conjunction to bring the core into a state of equilibrium when current is passed through them, substantially as described.

3. In an arc-lamp, the combination with a pair of separated iron rings, and a pair of coils wound upon said rings in the same direction and connected in series, of an armature-core for controlling the movable carbon adapted to move longitudinally through said coils and rings, whereby the combined action of the said coils will bring the core into a state of equilibrium without overmotion, substantially as described.

4. In an arc-lamp, the combination with a pair of separated iron rings, and a pair of coils wound upon said rings in the same direction and connected in series, a tube of nonmagnetic material within said rings, and an armature-core for controlling the movable carbon within said non-magnetic tube. substantially as described.

5. In an arc-lamp, the combination with a pair of separated iron rings, and a pair of coils wound upon said rings in the same direction and connected in series, a tube of nonmagnetic material within said rings and an armature located within said non-magnetic tube and forming a clutch for the movable carbon, substantially as described.

THOMAS HAMILTON-A DAMS.

Witnesses:

C. (1. REDFERN, A. ALBUTT. 

